France's state prosecutor on Monday began an effort to annul the marriage of a gay couple two days after they exchanged vows in the first such union in France. But one of the lawyers for the two men, Stephane Chapin and Bertrand Charpentier, said he would take the matter to the European Court of Human Rights if necessary.

Prosecutor Bertrand de Loze asked to have the couple appear in court. A date has not been set. The couple were married Saturday in the town of Begles, near Bordeaux, by town mayor Noel Mamere, a Green Party lawmaker known as a political provocateur. Justice minister Dominique Perben said that the Bordeaux court would be petitioned for nullification. Interior minister Dominique de Villepin said Mamere would be sanctioned.

"We're prepared to plead on the form and on the fundamentals as far as the European Court of Human Rights," said an attorney for the couple, Remy Giemza.

To charges that the couple took a fictitious address in Begles so that Mamere could perform the ceremony, the attorney said that this was not true. "The lease was signed in January," he said. Mamere said on Saturday that his decision to go ahead with the marriage despite numerous warnings from authorities was meant to be a step to end discrimination of all kinds, including of sexual orientation. Mamere risks a month's suspension from his post as mayor and a fine of up to $1,835, according to the Justice Ministry and the prime minister's office. The cabinet could take the matter further and issue a decree revoking the title of mayor, but officials have stressed that such a move would be unusual.